Sounding-board for pianos.



R. SCHMITT & J. RINDLISBAGHER.

SOUNDING BOARD POE PIANOS.

APPLICATION FILED MAY 23, 1910.

Patented Feb. 11, 1913.

CULUMBM PLANOGRAPH :0.,WASH1NGTON. n. cA

- rtreHARD sCHMrT'r AND JACOB RINDLISBACHER, or HAGEN, GERMANY.

SOUNDINGTBOARD FOR PIANOS.

Specication of Letters Patent.

Patented Feb. 11V, 191e.

"Application filed May 23,` 1910. Serial No. 563,033.

To all whom, itin/ay concern Y Be it known-that we, RioI-rAnn SoHMrrr andJACOB`R1NDLIsAcrrEu,Ksubjects of the Emperor of Germariy,"andfboth residing at ,`Hagen,` Germany, haveinvente'd a certain new'and useful Improvement in Sounding lBoards for Pianos,-of which the following isal specification. V

This invention relatesto improvements in sounding boards for pianos.

'A defect in pianos atfpresent in use is the lack of stabilityof the usual angular sound ing board. i Often, even after a short time, theboardyields to the stressof the strings, and the full tone of the instrument is gradually lost. Many attemptsrhavebeen made to impart greater stability to thesounding board. Double boards have been made,A or tension deviees,`for example metal ties, have been used for holding the board in position. These constructions, however, have not met with approval.

The present invention has for its object to provide a construction of sounding board by which the above mentioned defect is completely overcome, and which at the same time allows of the bridge being carried across the center of the sounding board, whereby in the mid-portion a full tone will be obtained. The mid-portion of the bridge intersects exactly the center of the board. The periphery of the board has for this purpose the form of a continuous curve Without corners. The uniform support of the board and absence of sharp corners render the interruption of vibration impossible.

A further great advantage of the invention is the great stability obtained against the stress of the strings. This stress is distributed uniformly over the periphery from every point. In grand pianos a board of circular form may'be used, but in small pianos, where there is but a limited supporting surface for` the bridge in treble and in bass an almost elliptic or elliptic sounding board is more suitable. In order to increase the stability of the lboard without diminishing the vibratory effect, t-he ribs are preferably arranged radially, extending outwardly from a supporting ring arranged clear of the board.

In the accompanying drawings which illustrate the invention, Figure 1 shows the board alone in front elevation wit-hout the in all` directions.

view of a portion of. the sounding'. board' showing the convexity of the ribs f and the beveled surface of thesupport for the sounding board.

Referring to Figs. l and 2, c denotes the elliptical sounding boardy arranged in the frame 0,. By means of the ribs fradiating from the center, .which ribs'are connected with a supporting ring g arranged clearA of the board, the latter acquires a form slightly convex toward the forward side, thus offering an elastic resistance to the stress of the strings, which stress owing to the elliptical form of the board is uniformly distributed sound board is obtained'by reasonofthe edge 0 of the frame a, against which the sound-board bears, being slightly beveled. Then the sound board is fixed to such beveled support it will assume a convex shape. It will be seen that the convex front faces of the ribs f, which are as usual glued to the sounding board, together with the beveled surface 0 of the support a, combine to flex or convex the sounding board toward the strings. The ribs are4 mounted in the support a, as clearly shown in Fig. 3. Such shaping is possible with an elliptical board and herein lies the particular advantage of the employment of such boards. An angular board for instance, although it could be bulged, could not be strained into convex shape of perfect-ly uniform deflection which is necessary to make it too highly elastic backing for the strings. The mid-portion of the bridge e (which is shown hollow) for the strings s, Fig. 2, passes through the center of the board c. This arrangement of the bridge e is rendered possible by reason of the fact that the board projects upwardly clear of and behind the tuning peg block b. The bass bridge h runs parallel with the circumference of the board in the form of an are. As is obvious, the ribs may be otherwise arranged, for instance, they may be parallel.

It will be seen by reference to Fig. l, that the sounding board has a continuously curved periphery, and that the curvature is convex throughout the periphery of the board, as regards the center of the board.

Having now described and ascertained the The convex shape ofthe naturenof our invention what We claim and desire "to secviire by Letters. Patent of the United4 States is:

1. A piano comprising in combination, an

elliptical sounding board, a support thereforA having beveled portions engaging opposite edges of .the board and serving to convex the Same toward the string side thereof, a bridge extending across the string side of the board and abreast of and across the center ofthe board, ribs shaped to conform to the convex deflection of and secured to and radially disposed on that side of the board opposite the string side to stiften the board and maintain convex deflection thereof, and a frame connected with the inner ends of the ribs and disposed abreast of but out of contact with the center of the board to prevent impairment of resonance at Such central portion, substantially as described.

'2. A ypiano comprising in combination, an elliptical sounding board, supporting means for conveXing the board toward the string side thereof, ribs secured to the board to stiEen the Same and maintain convex deiection of the. board, a bridge extending ,Copies o! this patent may be obtained for across the center of the board on the string side thereof, and rigid means connected with the ribs and disposed abreast'of but out of contact with the center of the board to prevent impairment of .resonance at such Central portion, substantially as described.

3. A piano comprising in combination, a sounding board having a continuously con- .veXly curved periphery, supporting means for convexing the board toward the string side thereof, ribs secured to the board to stiHen the same and Amaintain convex deflection ofthe board, a bridge extending across the center of thepboard on the string side thereof, and rigidmeans connected with the ribs and disposed abreast of but'out of contact With the center of the board to prevent impairment of resonance of such central portion, substantially as described.

In testimony whereof We aHiX our signatures in presence of tWo Witnesses.

RICHARD SCHMITT. JACOB RINDLISBACHER. Witnesses:

OTTO KNIG, W. DoNNEGA'r.

in. s.]A

ve cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

